Method for determining a position of a blocking element in a valve, a sensor system and use of a sensor system

Abstract

A method for determining a position of a blocking element in a valve having an operating device configured so that the blocking element moves between an open and a closed position in dependency of the direction in which the operating device is rotated. A sensor system is also provided for detecting a position of a blocking element in a valve.

The invention claimed is: 
     
       1. A method for determining a position of a blocking element in a valve comprising an operating device configured so that said blocking element moves between an open and a closed position in dependency of a rotational direction in which said operating device is rotated, said method comprising the steps of:
 connecting at least a reference part or a sensor of a sensor system to said operating device, so that said sensor system detects a rotation angle of said operating device and the rotational direction of said rotations, 
 calibrating said sensor system by
 rotating said operating device in a first direction until said blocking element reaches a first reference position in which said blocking element is in a fully closed or a fully open position, 
 storing said first reference position as said fully closed or said fully open position in a memory, 
 rotating said operating device in a second direction opposite said first direction until said blocking element performs a calibration stroke and reaches a second reference position of said fully closed or fully open position, 
 storing said second reference position as said fully closed or said fully open position in said memory, 
 rotating said operating device in said first direction again until said blocking element performs a first additional stroke and reaches said first reference position again and verifying correct calibration if a detected rotation angle of said calibration stroke is substantially the same as the detected rotation angle of said first additional stroke, 
 
 rotating said operating device while detecting said rotation angle of said operating device and said rotational direction of said rotations by means of said sensor system, and 
 determining the position of said blocking element based on said detected rotation angle and said detected rotational direction in relation to said first reference position and said second reference position. 
 
     
     
       2. A method according to  claim 1 , wherein correct calibration is only verified if said sensor system detects that the rotational direction of said calibration stroke is opposite the rotational direction of said first additional stroke. 
     
     
       3. A method according to  claim 1 , wherein said first reference position and said second reference position are stored in response to a store signal provided by an operator. 
     
     
       4. A method according to  claim 1 , wherein after having stored said second reference position, calibrating said sensor system further comprises the step of rotating said operating device in said second direction again after said blocking element performs said first additional stroke until said blocking element performs a second additional stroke and reaches said second reference position again and verifying correct calibration if the detected rotation angle of two of said calibration stroke, said first additional stroke and said second additional stroke are substantially the same. 
     
     
       5. A method according to  claim 4 , wherein correct calibration is only verified if said sensor system detects that the rotational direction of said calibration stroke and/or said second additional stroke is opposite the rotational direction of said first additional stroke. 
     
     
       6. A method according to  claim 1 , wherein said method further comprises the step of activating said sensor system, at least before storing said reference positions, in response to an activation signal provided by an operator. 
     
     
       7. A method according to  claim 6 , wherein said activation signal and/or a store signal is communicated wirelessly from an external wireless communication device. 
     
     
       8. A method according to  claim 7 , wherein said external wireless communication device is a mobile phone. 
     
     
       9. A sensor system for detecting a position of a blocking element in a valve comprising an operating device configured so that said blocking element moves between an open and a closed position in dependency of a direction in which said operating device is rotated, said sensor system comprising
 at least one reference part, wherein said at least one reference part is formed by a first magnet and a second magnet arranged on opposite sides of a rotational axis of said operating device and so that a respective polarity of said first magnet and second magnet is opposite to each other in a direction parallel with said rotational axis, 
 at least one sensor for detecting said at least one reference part, 
 wherein one of said at least one reference part and said at least one sensor comprises fixator for being held in a fixed position and wherein the other of said at least one reference part and said at least one sensor comprises connector for being rigidly connected to said operating device so that said at least one reference part and said at least one sensor is arranged to rotate in relation to each other if said operating device is rotated and wherein said at least one reference part and said at least one sensor are arranged so that a rotation angle and the direction of rotations of said operating device is detected by means of said at least one sensor, 
 wherein said at least one sensor system further comprises
 a memory for storing at least one reference position, 
 an input receiver for receiving a store signal arranged to activate storage of said at least one reference position, and 
 processing means arranged to determine said position of said blocking element based on said at least one reference position and input from said at least one sensor regarding rotation angle and said direction of rotations. 
 
 
     
     
       10. A sensor system according to  claim 9 , wherein said input receiver comprises a wireless input receiver for receiving said store signal wirelessly. 
     
     
       11. A sensor system according to  claim 9 , wherein said sensor system further comprises an external wireless communication device for communicating said store signal wirelessly to said input receiver. 
     
     
       12. A sensor system according to  claim 9 , wherein said sensor system further comprises a position indicator for communicating a determined position of said blocking element to a user. 
     
     
       13. A sensor system according to  claim 9 , wherein said sensor system further comprises a wireless position communicator for communicating a determined position of said blocking element wirelessly to an external wireless communication device. 
     
     
       14. A sensor system according to  claim 9 , wherein said sensor system further comprises a power unit for supplying electrical power to the at least one sensor and to a processor. 
     
     
       15. A sensor system according to  claim 9 , wherein said at least one reference part comprises at least one permanent magnet. 
     
     
       16. A sensor system according to  claim 9 , wherein said at least one sensor comprises at least one Hall effect sensor. 
     
     
       17. A sensor system according to  claim 9 , wherein said at least one sensor comprises two sensors arranged in a mutual displacement angle of 90 degrees in a plane perpendicular to said rotational axis of said operating device. 
     
     
       18. A sensor system according to  claim 9 , wherein said operating device comprises an extension device extending from said valve. 
     
     
       19. A sensor system according to  claim 9 , wherein said at least one reference part or said at least one sensor is held in a fixed position in relation to said valve. 
     
     
       20. A sensor system according to  claim 9 , wherein said least one reference position comprises at least a first reference position corresponding to said blocking element being in one of a fully closed or a fully open position, and a second reference position corresponding to said blocking element being in the other of said fully closed or fully open position. 
     
     
       21. A sensor system according to  claim 9 , wherein at least said at least one sensor, said memory, said input receiver and said processor are formed as a single interconnected unit. 
     
     
       22. A sensor system according to  claim 9 , wherein said sensor system further comprises a temperature sensor. 
     
     
       23. A sensor system according to  claim 9 , wherein said memory comprises a memory for storing at least two reference positions. 
     
     
       24. A sensor system according to  claim 9 , wherein the valve is a multi-turn valve.